KVM: s390: infrastructure to kick vcpus out of guest state

To ensure vcpu's come out of guest context in certain cases this patch adds a
s390 specific way to kick them out of guest context. Currently it kicks them
out to rerun the vcpu_run path in the s390 code, but the mechanism itself is
expandable and with a new flag we could also add e.g. kicks to userspace etc.

Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

1 files changed, 5 insertions, 0 deletions

diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 90d9d1ba258b..1d65f6277166 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -490,6 +490,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
 
         vcpu_load(vcpu);
 
+rerun_vcpu:
         /* verify, that memory has been registered */
         if (!vcpu->kvm->arch.guest_memsize) {
                 vcpu_put(vcpu);
@@ -509,6 +510,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
                 vcpu->arch.sie_block->gpsw.addr = kvm_run->s390_sieic.addr;
                 break;
         case KVM_EXIT_UNKNOWN:
+        case KVM_EXIT_INTR:
         case KVM_EXIT_S390_RESET:
                 break;
         default:
@@ -522,6 +524,9 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
                 rc = kvm_handle_sie_intercept(vcpu);
         } while (!signal_pending(current) && !rc);
 
+        if (rc == SIE_INTERCEPT_RERUNVCPU)
+                goto rerun_vcpu;
+
         if (signal_pending(current) && !rc)
                 rc = -EINTR;